JP7107773B2 - Endoscope - Google Patents

Description

The present disclosure relates to endoscopes.

A small-diameter angioscopic catheter that uses a guide wire having an outer diameter of about 0.35 mm inserted into a blood vessel in advance and enables smooth access to an affected area is known (see, for example, Patent Document 1, etc.). . This diameter-reduced angioscopy catheter has a main body of an optical fiber bundle with an outer diameter of about 0.4 mm, and has a tip with a circular cross section and an optical lens at its distal end. The tip is provided with a guidewire passage lumen and is equipped with a guidewire. The reduced diameter angioscopic catheter can be easily inserted to the target site along the guidewire by passing the guidewire through the guidewire passage lumen. In a reduced diameter angioscopic catheter, an intravascular image is captured by an optical lens and transmitted proximally through a fiber optic bundle. The transmitted image can be displayed on a display device or the like.

Utility Model Registration No. 3188206

However, although an optical lens is arranged at the distal end of the diameter-reduced angioscope catheter of Patent Document 1, an imaging element for capturing an image is not arranged. Here, in order to capture a high-quality image of a subject into which the endoscope is inserted (for example, a diseased part in the subject, which is a human body), considering the configuration in which an imaging device is provided at the insertion tip of the endoscope, the tip While downsizing the image pickup device, it is necessary to take measures against static electricity so that the image pickup device will not be destroyed or otherwise damaged by static electricity from the subject. Patent Document 1 does not recognize such a problem.

The present disclosure has been devised in view of the conventional circumstances described above, and an object thereof is to provide an endoscope that can protect an imaging device from destruction by static electricity while suppressing an increase in diameter with a simple structure.

The present invention is an endoscope, comprising: an imaging element having a light receiving surface on which imaging light is imaged; a sensor circuit unit provided on the back surface opposite to the light receiving surface ; The endoscope includes a lens that is provided on the distal end side of the imaging element in the insertion direction of the endoscope and that allows the imaging light to enter the imaging element , and a housing part that houses the lens and the imaging element, a conductive member extending from the distal end face of the endoscope in the insertion direction ; a grounding member for grounding the conductive member ; and a fixing resin that fixes the at a distance from the conductive member .

Advantageous Effects of Invention According to the present disclosure, in an endoscope, it is possible to protect an imaging element from destruction due to static electricity while suppressing an increase in diameter with a simple structure.

FIG. 2 is a perspective view showing an appearance example of the distal end side in the insertion direction of the endoscope according to Embodiment 1; The top view of the endoscope shown in FIG. The side view of the endoscope shown in FIG. Front view of the endoscope shown in FIG. Side view with the sheath of FIG. 3 cut away Rear view of the holder seen from the cross section of the sheath's circular part Rear view of the holder viewed from the cross section of the elliptical portion of the sheath AA sectional view of FIG. BB sectional view of FIG. Front view of a holder according to another configuration example Side sectional view of the holder shown in FIG. FIG. 3 is a perspective view of another configuration example having a lumen tube as a guidewire lumen; Front view of lumen tube shown in FIG. Side sectional view of FIG. Side view of imaging unit Side cross-sectional view of the tip of the endoscope in the insertion direction showing the insulating structure of the sensor circuit section

Hereinafter, embodiments specifically disclosing an endoscope according to the present disclosure will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid unnecessary verbosity in the following description and to facilitate understanding by those skilled in the art. It should be noted that the accompanying drawings and the following description are provided to allow those skilled in the art to fully understand the present disclosure and are not intended to limit the claimed subject matter.

FIG. 1 is a perspective view showing an example of the appearance of an endoscope 11 according to Embodiment 1 on the distal end side in the insertion direction. In the following description, the directions used for description follow the description of the directions in FIG. Here, left and right are directed forward from the tip of the endoscope 11 in the direction of insertion in the vertical direction shown in FIG. 1, with the right hand side corresponding to the right side and the left hand side corresponding to the left side.

An endoscope 11 according to Embodiment 1 includes a lens 13 (see FIG. 8), an imaging element 15 (see FIG. 8), a holder 17, a sheath 19, and a conductive member (for example, a metal cylinder in FIG. 21) and a grounding member (metal wire 23 in FIG. 9) as main components.

The endoscope 11 is inserted into a guide catheter (not shown) inserted so as to accommodate the guide wire 25 after the guide wire 25 is inserted into the subject (eg, human body) during surgery or examination, for example. can be used by being inserted into the The guide catheter is inserted through, for example, a blood vessel within the subject. For example, the guide catheter has an outer diameter of 1.8 mm and an inner diameter of 1.5 mm. A guide wire 25 is passed through the guide catheter. The guide wire 25 has an outer diameter of 0.35 mm, for example. The endoscope 11 is passed through the guide catheter together with this guide wire 25 . Therefore, the endoscope 11 has a guide wire hole 27 for passing the guide wire 25 therethrough. Since the endoscope 11 according to Embodiment 1 has the guide wire hole 27 and is passed through the guide catheter, the maximum outer diameter D (see FIG. 3) is set to 1.35 mm or less, for example.

The endoscope 11 is provided with a holder 17 at the distal end of the insertion portion 29 in the insertion direction. The insertion portion 29 is covered with the sheath 19 over most of its entire length. The sheath 19 is made of, for example, a flexible resin material and has a tubular shape (that is, tubular shape). The sheath 19 can have a single wire, multiple wires, or a braided tensile strength wire on the inner peripheral side for the purpose of imparting strength, for example. As the tensile strength wire, aramid fiber such as poly-p-phenylene terephthalamide fiber, polyarylate fiber, polyparaphenylene benzobisoxazole fiber, polyester fiber such as polyethylene terephthalate fiber, nylon fiber, tungsten fine wire or stainless steel fine wire etc. can be cited as an example. The sheath 19 has a perfect circular portion 31 whose cross-sectional shape in the direction perpendicular to the axis or the optical axis of the lens 13 is a perfect circle. A flat portion 33 having an elliptical cross-sectional shape is formed by deforming and fitting so as to form a flat portion 33 .

The holder 17 to which the sheath 19 is connected exposes the lens cover glass 35 on the tip surface. A lens cover glass 35 may be integrally fixed to the surface of the lens 13 as the imaging optical system. In Embodiment 1, the lens cover glass 35 integrally fixed to the lens 13 is exposed on the tip surface of the holder 17 . The lens 13 is provided at the distal end in the insertion direction to take in imaging light (that is, allows light from a subject such as an affected area in the subject to enter). In addition, light emitting end faces of a plurality of illumination optical fibers 37 continuously arranged in the vertical direction are arranged on the tip end face of the holder 17 on the right and left sides of the lens cover glass 35 .

The holder 17 has a raised portion 41 on the upper side of an elliptical flat cylindrical portion 39 whose long axis is the left and right. The guide wire hole 27 is bored through the raised portion 41 in the extending direction of the sheath 19 . The holder 17 covers the lens 13 and the imaging element 15 that constitute the distal end portion of the endoscope 11 and includes a guide wire hole 27 through which the guide wire 25 passes.

FIG. 2 is a plan view of the endoscope 11 shown in FIG. 1. FIG. The sheath 19 has a flat portion 33 wider in the horizontal direction than the circular portion 31 at the distal end of the sheath (that is, the distal end portion of the sheath 19). That is, the sheath 19 has the outer shape of the flat portion 33 at the distal end of the sheath (see above), but the flat portion 33 converges toward the rear end side from the distal end of the sheath to have the outer shape of the circular portion 31 . The holder 17 is slightly larger than the flat portion 33 in the lateral direction, but may be formed with the same width as the flat portion 33 . The guide wire hole 27 is bored at the top of the raised portion 41 at the central portion in the direction along the axis of the holder 17 .

FIG. 3 is a side view of the endoscope 11 shown in FIG. 1. FIG. The raised portion 41 of the holder 17 has a mountain shape. In the endoscope 11 according to Embodiment 1, the total height up to the top of the holder 17 is set to the maximum outer diameter D (that is, the maximum outer diameter of the endoscope 11). The angle of inclination θ of this chevron is the same on the front end side in the insertion direction and on the rear end side in the insertion direction. The inclination angle .theta. This allows the endoscope 11 to be smoothly inserted into and removed from blood vessels and catheters. Note that the inclination angle is not limited to the angle value described above, and the inclination angle θ of the chevron may not be the same between the front end side in the insertion direction and the rear end side in the insertion direction.

FIG. 4 is a front view of the endoscope 11 shown in FIG. 1. FIG. The holder 17 has only two holes on its distal end surface, that is, the guide wire hole 27 and the observation hole 43 in which the lens cover glass 35 and the illumination optical fiber 37 are arranged. The lens cover glass 35 and the illumination optical fiber 37 arranged inside the observation hole 43 are stably fixed by the black resin 45 filled in the observation hole 43 .

The holder 17 is formed so that the left and right width W2 sandwiching the guide wire hole 27 is smaller than the left and right width W1 sandwiching the observation hole 43 when viewed from the front of the distal end surface where the guide wire hole 27 and the observation hole 43 are vertically arranged. be. As a result, the outer shape of the holder 17 is a so-called teardrop shape when viewed from the front, and a clear liquid flows into the gap between the catheter or the blood vessel and the endoscope 11 to easily maintain the field of view.

FIG. 5 is a cutaway side view of the sheath 19 of FIG. The holder 17 has a tubular sheath fitting portion 47 that protrudes rearward from the rear end of the flat cylindrical portion 39 (an example of the camera housing portion). The sheath tip is fitted and connected to the outer periphery of this sheath fitting portion 47 . In the holder 17, the flat columnar portion 39, the raised portion 41 and the sheath fitting portion 47 are integrally formed of metal. For example, SUS (stainless steel) can be used as the metal. The sheath 19 is formed with a thickness t of 75 μm, for example. The sheath 19 is connected to a sheath fitting portion 47 extending from the rear end portion of the holder 17, and a cable 49 conductively connected to the imaging element 15 and the illumination optical fiber 37 are inserted inside.

6 is a rear view of the holder 17 viewed from the cross section of the circular portion 31 of the sheath 19. FIG. The sheath 19 has a circular portion 31 on the rear end side in the insertion direction. The sheath 19 is gradually flattened toward the sheath fitting portion 47 , and becomes an ellipse following the outer circumference of the sheath fitting portion 47 at the fitting portion with the sheath fitting portion 47 . The circular portion 31 is substantially in contact with the guidewire bore 27 . The guidewire aperture 27 is drilled into the ridge 41 leaving a bridge 51 at the top. The thickness n of the bridging portion 51 is set to 50 μm, for example.

The imaging element 15 can be seen inside the sheath fitting portion 47 . The imaging device 15 has, for example, four bumps 53 on its back surface. Each bump 53 is fixed by soldering to each of a plurality of core wires 55 bundled as a cable 49 . As a result, in the imaging device 15, the cable 49 and the sensor circuit section 57 (see FIG. 15) are conductively connected. A ground member is passed through the sheath 19 along with the cable 49 . The grounding member is conductively connected to the sheath fitting portion 47 of the holder 17 .

7 is a rear view of the holder 17 seen from the cross section of the elliptical portion of the sheath 19. FIG. The sheath fitting portion 47 protruding rearward from the holder 17 has an elliptical cross-sectional shape in the direction perpendicular to the axis of the sheath 19, with one end of the short axis of the sheath 19 close to the guide wire hole 27. . The annular portion sandwiched between the cross section of the sheath 19 and the end surface of the sheath fitting portion 47 in FIG. is.

FIG. 8 is a cross-sectional view taken along line AA of FIG. In the endoscope 11, the lens cover glass 35 and the lens 13 are formed in the same outer shape by a flat square prism (for example, a regular square prism) that is short in the axial direction. The lens 13 has a concave portion formed on the surface opposite to the lens cover glass 35 . The lens 13 has a convex lens surface 59 facing the imaging element 15 on the bottom surface of this concave portion. The convex lens surface 59 is arranged to face the imaging element 15 via air, and functions as an effective element portion of the lens 13 (that is, a portion that refracts incident light).

The surface of the imaging device 15 facing the lens 13 serves as a light receiving surface. The imaging device 15 is provided behind the lens 13 so that the imaging light is imaged on the light receiving surface. A sensor cover glass 61 is integrally fixed to the light receiving surface of the imaging device 15 . The strength of the imaging device 15 is ensured by being integrated with the sensor cover glass 61 . The lens cover glass 35 , the lens 13 , the sensor cover glass 61 and the imaging device 15 constitute an imaging unit 63 .

9 is a cross-sectional view taken along the line BB of FIG. 4. FIG. A camera housing portion 65 is formed inside the holder 17 . The camera housing portion 65 houses the imaging unit 63 . The camera housing portion 65 is formed inside the flat cylindrical portion 39 . The sheath tip of the holder 17 is connected to the sheath fitting portion 47 extending from the rear end of the camera housing portion 65 . The endoscope 11 is substantially in contact with the guide wire 25 at the circular portion 31 of the sheath 19 . In the endoscope 11, the total height H including the guide wire 25 in the circular portion 31 is approximately 1.3 mm, for example.

The endoscope 11 is deformed into a horizontally long ellipse by fitting the sheath 19 into the sheath fitting portion 47 below the guide wire 25 passed through the guide wire hole 27 . As a result, a gap 67 is formed between the guide wire 25 and the sheath 19 at the distal end of the endoscope 11 in the insertion direction.

The endoscope 11 includes a conductive member covering the lens 13 and the imaging device 15 . The conductive member is grounded to GND (ground) through a grounding member. In Embodiment 1, this conductive member becomes the holder 17 .

Further, in Embodiment 1, the metal wire 23 is used as the grounding member. Metal wire 23 extends along cable 49 within sheath 19 . The metal wire 23 is connected to an insulated ground portion of an insulated circuit provided in a video processor (not shown) to which the endoscope 11 is connected via a plug portion (not shown) whose proximal end is connected to the insertion portion 29 . Connected.

In the endoscope 11, the entire holder 17 made of metal can be a portion to which static electricity is applied. Static electricity is applied to the holder 17 of the endoscope 11, for example, during an operation or examination, and the current flowing from the holder 17 to the metal wire 23 is released to the insulated ground portion of the circuit to be insulated via the plug portion. This suppresses static electricity from being applied to the sensor circuit section 57 of the imaging element 15 .

For the endoscope 11 used as a medical endoscope, for example, it is necessary to consider preventing leakage current from flowing into a patient, who is a subject. Therefore, a gap G (see FIG. 16) may be provided to insulate the metal wire 23 that induces static electricity from the holder 17 serving as the patient contact portion. The static-inducing metal wire 23 is connected through an electrically insulating circuit to an insulated ground with sufficiently reduced leakage current. In this manner, the metal wire 23 for inducing and releasing static electricity is installed between the endoscope 11 and the holder 17 to release it to the insulated ground portion. The endoscope 11 having such a configuration solves the problem peculiar to electronic endoscopes in which the imaging device 15 is mounted at the tip, and protects the imaging device 15 from static electricity. is done.

Alternatively, the conductive member may be directly conductively connected to the ground member without providing a gap G. In this case, a protective element such as an ESD (Electro Static Discharge) suppressor is provided between the metal wire 23 and GND.

FIG. 10 is a front view of a holder 69 according to another configuration example. In this configuration example, the holder 69 is not provided with the guide wire hole 27 . A configuration that includes a conductive member and a grounding member at the distal end in the insertion direction is also useful for an endoscope that does not have a guide wire hole 27 as shown in FIG. In this case, the holder 69 is formed cylindrical, for example. The holder 69 may be made of metal or resin. When the holder 69 is made of resin, the metal cylindrical portion 21 which is a rigid and conductive member is provided inside the holder 69 . The metal cylindrical portion 21 can have a thickness of, for example, 30 to 50 μm.

FIG. 11 is a side sectional view of holder 69 shown in FIG. The metal cylindrical portion 21 accommodates the imaging unit 63 inside. The imaging unit 63 is stably fixed to the inner circumference of the metal cylindrical portion 21 with, for example, the lens cover glass 35 , the lens 13 , and a part of the sensor cover glass 61 with a black resin 45 . The metal cylindrical portion 21 is connected to the metal wire 23 at its rear end sufficiently spaced from the imaging device 15 of the imaging unit 63 .

FIG. 12 is a perspective view of another configuration example having a lumen tube 71 as a guidewire lumen. The endoscope 11 may be provided with the guide wire hole 27 by using a perforated member having a plurality of holes. This porous member can be referred to as the guidewire lumen. Among the guide wire lumens, a tubular one is referred to as a lumen tube 71 . The endoscope 11 uses the lumen tube 71 at the rear end of the long cylindrical holder 73 which is the tip in the insertion direction, so that the guide wire 25 can pass through the guide wire hole 27 of the lumen tube 71 .

13 is a front view of the lumen tube 71 shown in FIG. 12. FIG. In this case, the holder 73 can have a simple structure without the raised portion 41 . The holder 73 has an observation hole 43 in which the lens cover glass 35 and the illumination optical fiber 37 are arranged on its tip surface. The lens cover glass 35 and the illumination optical fiber 37 arranged inside the observation hole 43 are stably fixed by the black resin 45 filled in the observation hole 43 .

14 is a side sectional view of FIG. 12; FIG. The endoscope 11 has a tubular portion equivalent to the sheath 19, and the sheath 19 can be omitted by using the lumen tube 71 in which the guide wire hole 27 is formed only at the tip of the tubular portion in the insertion direction. Thereby, the holder 73 can be simplified.

In other words, in the endoscope 11 shown in FIGS. 1 to 9, the conductive member (that is, the holder 17) formed with the guide wire hole 27 also serves as the guide wire lumen. On the other hand, in the configuration using the lumen tube 71, the holder 73 can be simplified, but the portion of the lumen tube 71 where the guide wire hole is formed becomes long, and the bending performance deteriorates. In contrast, according to the endoscope 11 in which the guide wire hole 27 is formed in the holder 17 made of metal as described above, the entire length of the holder 17 is shortened, so good bending performance is ensured.

FIG. 15 is a side view of the imaging unit 63. FIG. In the imaging unit 63 of the endoscope 11 , the lens 13 is integrally fixed to the light receiving surface of the imaging device 15 . More specifically, the integrated lens cover glass 35 and lens 13 formed with the same outer shape are fixed to the sensor cover glass 61 fixed to the light receiving surface of the imaging device 15 . Here, in the imaging unit 63 , the outer shapes of the lens cover glass 35 and the lens 13 are formed larger than the sensor cover glass 61 . Furthermore, the sensor cover glass 61 is formed larger than the outer shape of the sensor circuit section 57 of the imaging device 15 . In other words, the lens 13 , the sensor cover glass 61 , and the sensor circuit section 57 gradually become smaller through the stepped section 75 .

FIG. 16 is a side cross-sectional view of the distal end in the insertion direction of the endoscope 11 showing the insulating structure of the sensor circuit section 57. As shown in FIG. In the endoscope 11, the sensor circuit portion 57 of the imaging element 15 and the conductive member (the inner surface of the holder 17) do not come into contact with each other.

In addition, the endoscope 11 has a higher insulation resistance (distance L) between the sensor circuit portion 57 and the conductive member (inner surface of the holder 17) than the conductive member (sheath fitting portion 47) and the grounding member (metal wire). 23) has a small insulation resistance (gap G). That is, the dielectric breakdown distance between the holder 17 and the metal wire 23 is set smaller than the dielectric breakdown distance between the holder 17 and the sensor circuit section 57 (L>G).

Next, the operation of the configuration of the endoscope 11 according to the first embodiment will be described.

An endoscope 11 according to Embodiment 1 has a lens 13 that is provided at the tip in the direction of insertion into a subject and that receives imaging light. The endoscope 11 has an imaging device 15 which is connected to the rear end of the lens 13 and forms an image of imaging light. The endoscope 11 has a holder 17 that covers the lens 13 and the imaging element 15 and has a guide wire hole 27 through which a guide wire 25 inserted into the subject passes. The endoscope 11 has a flexible tubular sheath 19 connected to the rear end of the holder 17 and through which a cable 49 conductively connected to the imaging element 15 is inserted.

In the endoscope 11 according to Embodiment 1, the sheath 19 is connected to the rear end portion of the holder 17 . Since the sheath 19 is connected to the rear end portion of the holder 17, the outer diameter of the holder 17 can be made smaller by the thickness of the sheaths 19 on both sides in the diametrical direction, compared to a configuration in which the outer circumference of the sheath 19 is covered and attached. An increase in the maximum outer diameter of the mirror can be suppressed. In addition, since the endoscope 11 accommodates both the lens 13 and the imaging device 15 in the holder 17 provided at the tip in the insertion direction, imaging light can be guided using an optical fiber bundle as in the prior art. It is possible to obtain a high-quality captured image as compared with the image capturing method in which the captured image is displayed by pressing the camera. Furthermore, since the holder 17 of the endoscope 11 has the guide wire hole 27 , the guide wire 25 can be passed through the guide wire hole 27 and can be easily inserted along the guide wire 25 to the target site.

Therefore, according to the endoscope 11 according to Embodiment 1, in the configuration having both the lens 13 and the imaging element 15 at the distal end and the guide wire hole 27, the diameter of the distal end in the insertion direction can be reduced.

In the endoscope 11 , the holder 17 has a camera housing portion 65 inside which houses the lens 13 and the image sensor 15 , and the distal end of the sheath 19 is connected to the rear end of the camera housing portion 65 . .

In this endoscope 11 , the distal end of the sheath 19 is connected to the rear end of the camera housing portion 65 . The tip in the insertion direction is composed of a lens 13, an imaging device 15, and a holder 17 covering them. As a result, the holder 17 can form the camera housing portion 65 with a size capable of housing only the minimum necessary components, and the endoscope 11 can be easily reduced in diameter and size in the insertion direction.

Further, in the endoscope 11 , the holder 17 has a cylindrical sheath fitting portion 47 projecting rearward from the rear end of the camera housing portion 65 . The distal end of the sheath 19 is fitted and connected to the outer periphery of the sheath fitting portion 47 .

In this endoscope 11, the camera housing portion 65 has a sheath fitting portion 47 protruding rearward from the rear end. The sheath fitting portion 47 is formed in a tubular shape. The holder 17 can integrally form the camera housing portion 65 and the sheath fitting portion 47 . The sheath 19 is fixed by fitting the inner periphery to the outer periphery of the sheath fitting portion 47 . The sheath fitting portion 47 is formed in a size such that the outer shape of the fitted sheath 19 does not protrude outside the outer shape of the holder 17 . An adhesive, for example, is used to fix the sheath 19 and the sheath fitting portion 47 together. By fitting the sheath fitting portion 47 to the outer periphery of the sheath fitting portion 47, a large bonding area can be secured. As a result, the sheath 19 and the holder 17 can ensure greater connection strength compared to a connection structure in which the end surfaces are abutted against each other. Moreover, since a large bonding area can be ensured, the waterproof performance at the joint between the holder 17 and the sheath 19 can also be improved.

The cross-sectional shape of the endoscope 11 in the direction perpendicular to the axis of the sheath fitting portion 47 is an ellipse with one end of the short axis close to the guide wire hole 27 .

In this endoscope 11, the cross-sectional shape of the sheath fitting portion 47 is an ellipse. Therefore, the cross-sectional shape of the sheath 19 fitted to the outer circumference of the sheath fitting portion 47 also becomes an ellipse following this. One end of the short axis of this ellipse is oriented close to the guidewire hole 27 . Therefore, below the guide wire 25 passed through the guide wire hole 27, the sheath 19 connected to the sheath fitting portion 47 is deformed into a laterally long ellipse. A gap 67 is thereby formed between the guide wire 25 and the sheath 19 . In the endoscope 11, the gap 67 prevents the guide wire 25 from interfering with the sheath 19, facilitating bending of the holder 17 in the vicinity of the rear side, thereby improving the insertability. Further, by shortening the vertical dimension of the sheath 19, the outer diameter dimension of the distal end portion of the endoscope 11 can be reduced.

Also, the endoscope 11 is passed through a guide catheter, and a transparent liquid is introduced into the blood vessel through the guide catheter to maintain the field of view. At this time, the external shape when viewed from the front becomes a so-called teardrop shape, and the bias in the ejection direction of the liquid can be suppressed.

Further, in the endoscope 11, the holder 17 is made of metal (that is, formed using metal having rigidity).

In this endoscope 11, a guide wire 25 is passed through a guide wire hole 27, and the holder 17 is inserted along the guide wire 25 to a target site. At that time, the holder 17 suppresses abrasion of the guide wire hole 27 due to sliding contact with the guide wire 25 as compared with the case where the holder 17 is made of resin or ceramics.

Further, in the endoscope 11, the holder 17 has only two holes on its distal end surface, the guide wire hole 27 and the observation hole 43 in which the lens 13 and the illumination optical fiber 37 are arranged.

In this endoscope 11 , the distal end surface of the holder 17 has only the observation hole 43 in addition to the guide wire hole 27 . A lens 13 and an illumination optical fiber 37 are arranged in the observation hole 43 . The illumination optical fibers 37 are generally arranged in a pair with the lens 13 interposed therebetween in order to obtain a good illumination effect. If these exclusive holes are formed in the holder 17, for example, four holes are required on the tip surface. An angioscope that is passed through a guide catheter (inner diameter of about 1.5 mm) preferably has an outer diameter of at least 1.4 mm or less. Forming four holes in such a small-diameter distal end face can be an obstacle to realizing a reduction in manufacturing cost and mass productivity of the holder 17 . Therefore, in the endoscope 11 , the lens 13 and the illumination optical fiber 37 are arranged in the same room as one observation hole 43 . As a result, the endoscope 11 relaxes the processing limit, reduces the manufacturing cost, and secures mass productivity. Note that the observation hole 43 is filled with a black resin 45 . The black resin 45 filled in the observation hole 43 forms partitions separating the lens 13 and the illumination optical fiber 37 from each other. As a result, the endoscope 11 suppresses illumination light from entering the lens 13 from the illumination optical fiber 37 . In addition, by black-coating the periphery of the illumination optical fiber 37 , it is possible to suppress the incidence of the illumination light from the illumination optical fiber 37 to the lens 13 . In that case, the filling resin need not be black.

Further, the holder 17 is formed so that the lateral width sandwiching the guide wire hole 27 is smaller than the lateral width sandwiching the observation hole 43 when viewed from the front of the distal end surface where the guide wire hole 27 and the observation hole 43 are vertically arranged. be.

In this endoscope 11 , the holder 17 is formed so that the width across the guide wire hole 27 is smaller than the width across the observation hole 43 . That is, the holder 17 is formed in a so-called teardrop shape when viewed from the front. As described above, the endoscope 11 is passed through the guide catheter, and a transparent liquid is allowed to flow into the blood vessel from the guide catheter to maintain the field of view. At this time, since the endoscope 11 has a teardrop shape, it is possible to secure a sufficient gap between the endoscope 11 and the inner diameter of the guide catheter, which is the circumscribed circle. As a result, the endoscope 11 can more reliably secure a fluid discharge space than when the holder 17 is a perfect circle when viewed from the front.

The endoscope 11 also has a lens 13 that is provided at the tip in the direction of insertion into the subject and receives imaging light. The endoscope 11 has an imaging device 15 which is connected to the rear end of the lens 13 and forms an image of imaging light. The endoscope 11 has a conductive member (for example, the holder 17 and the metal cylindrical portion 21) that covers the lens 13 and the imaging element 15. As shown in FIG. The endoscope 11 has a grounding member (for example, a metal wire 23) for grounding the conductive member described above to GND (ground).

In this endoscope 11, an imaging device 15 provided together with a lens 13 is covered with a conductive member at the tip in the insertion direction. This conductive member is grounded to GND (ground) through a grounding member. The grounding member may be, for example, a metal wire 23 or a metal braid of a braided tube. The conductive member that covers the lens 13 and the imaging element 15 receives imaging light (that is, light from an object such as an affected part in the subject) from the front of the tip in the insertion direction, and extends the grounding member backward in the insertion direction. exist. Therefore, the conductive member is open at the front end in the insertion direction and the rear end in the insertion direction. In other words, the conductive member has a cylindrical shape. For example, if the conductive member is a cylinder, it can surround the imaging device 15 from 360 degrees around the axis. As a result, the imaging element 15 can be accurately shielded against static electricity flying from 360-degree directions. In addition, the endoscope 11 can be made smaller than a structure in which a sufficient space is set and insulated without providing a conductive member. As a result, the endoscope 11 can improve the operational reliability of the imaging device 15 while realizing a small diameter.

Therefore, according to the endoscope 11 according to Embodiment 1, it is possible to protect the imaging device 15 from destruction due to static electricity while suppressing an increase in diameter with a simple structure, and to ensure safe use.

Also, since the imaging element 15 is surrounded inside the conductive member, static electricity does not fly from the grounding member conductively connected to the end of the conductive member. Therefore, a bare conductor or the like with no insulating coating can be used as the grounding member. As a result, the diameter of the sheath 19 through which the grounding member is inserted can be reduced to the extent that the configuration of the insulating coating can be omitted from the outer periphery of the grounding member.

The endoscope 11 further has a guide wire lumen provided at the distal end in the direction of insertion and having a guide wire hole 27 through which the guide wire 25 passes.

This endoscope 11 is provided with a guide wire lumen at the distal end in the insertion direction. In this case, the conductive member can be provided inside the guidewire lumen. The material of the guide wire lumen may be resin or metal. The guide wire lumen can be, for example, a flexible resin lumen tube 71 . Lumen tube 71 may be integrally molded with sheath 19 connected to the rear of the conductive member. The lumen tube 71 has a guidewire hole 27 through which the guidewire 25 passes. The endoscope 11 is provided with the lumen tube 71, the conductive member, and the imaging element 15 at the tip in the insertion direction, thereby protecting the imaging element 15 from static electricity and obtaining a high-quality observation image. In addition to this, the endoscope 11 can be easily inserted into the target site along the guide wire 25 by passing the guide wire 25 through the guide wire hole 27 of the lumen tube 71 .

In addition, in the endoscope 11, the conductive member in which the guide wire hole 27 is formed also serves as the guide wire lumen.

In this endoscope 11, a guide wire hole 27 is formed in the conductive member. A conductive member having a guide wire hole 27 is equivalent to the holder 17 described above. That is, the endoscope 11 can omit the lumen tube 71 by using the holder 17 to configure the distal end in the insertion direction.

Also, in the endoscope 11, the sensor circuit portion 57 of the imaging element 15 and the conductive member do not contact each other (that is, they are arranged apart from each other).

In the endoscope 11 , static electricity flying to the conductive member and flowing to the grounding member is prevented from being short-circuited to the imaging device 15 . This prevents damage such as destruction of the imaging device 15 due to static electricity flowing through the sensor circuit section 57 .

In addition, the endoscope 11 is integrally fixed so that the lens 13 forms an image of imaging light (that is, light from a subject such as an affected part in the subject) on the light receiving surface of the imaging device 15 . . The outer diameter of the lens 13 (that is, the cross-sectional shape in the direction perpendicular to the optical axis of the lens 13) is the outer diameter of the sensor circuit section 57 of the imaging device 15 (that is, the shape in the direction perpendicular to the optical axis of the lens 13). cross-sectional shape).

In the endoscope 11, in the manufacturing process, the integrated lens 13 and imaging element 15 are inserted inside the conductive member as an imaging unit 63 and assembled. At this time, even if the imaging unit 63 contacts the inner surface of the conductive member, the lens 13 contacts the conductive member, and the sensor circuit section 57 is less likely to contact the inner surface of the conductive member. As a result, the risk of the sensor circuit section 57 coming into contact with the conductive member can be reduced during mass production, and productivity can be improved.

Also, in the endoscope 11, the insulation resistance between the conductive member and the grounding member is smaller than the insulation resistance between the sensor circuit section 57 and the conductive member.

In this endoscope 11, the distance (gap G) between the conductive member and the grounding member is set smaller than the distance L between the sensor circuit portion 57 and the conductive member. There is no particular difficulty in electrically connecting the conductive member and the ground member. As long as the conductive member and the ground member are conductively connected, it is sufficient to ensure a slight distance between the sensor circuit section 57 and the conductive member. For example, a dielectric strength voltage of 200 V can be obtained by securing a spatial distance of 10 μm. As a result, a large current due to the high voltage of static electricity can be reliably passed through the grounding member, and the imaging element 15 can be protected from destruction.

Also, the endoscope 11 has a metal wire 23 as a grounding member.

In this endoscope 11, by using the metal wire 23 as the grounding member, it is possible to simultaneously obtain the grounding function of the conductive member and the pushability due to the rigidity of the metal wire 23 (so-called pushability that does not easily buckle). can.

Various embodiments have been described above with reference to the drawings, but it goes without saying that the present disclosure is not limited to such examples. It is obvious that a person skilled in the art can conceive of various modifications, modifications, substitutions, additions, deletions, and equivalents within the scope of the claims. Naturally, it is understood that it belongs to the technical scope of the present disclosure. In addition, the constituent elements of the various embodiments described above may be combined arbitrarily without departing from the spirit of the invention.

INDUSTRIAL APPLICABILITY The present disclosure is useful as an endoscope that can protect an imaging element from destruction due to static electricity while suppressing an increase in diameter with a simple structure.

11 Endoscope 13 Lens 15 Imaging element 17 Holder 19 Sheath 21 Metal cylindrical portion 23 Metal wire 25 Guide wire 27 Guide wire hole 37 Optical fiber for illumination 43 Observation hole 47 Sheath fitting portion 49 Cable 57 Sensor circuit portion 65 Camera housing portion

Claims (7)

an endoscope,
an imaging device having a light receiving surface on which imaging light is imaged, and a sensor circuit unit provided on the back surface opposite to the light receiving surface;
a lens that is provided on the distal end side of the imaging device in a direction in which the endoscope is inserted into the subject and that allows the imaging light to enter the imaging device ;
a conductive member having an accommodating portion that accommodates the lens and the imaging element and extending from the distal end surface of the endoscope in the insertion direction ;
a grounding member that grounds the conductive member;
a fixing resin that extends from the distal end surface of the endoscope in the accommodating portion and fixes the imaging element and the lens while separating them from the conductive member;
comprising
Endoscope. further comprising a guidewire lumen provided at the distal end in the insertion direction and having a guidewire hole through which the guidewire passes;
The endoscope according to claim 1. the conductive member is the guidewire lumen ;
the guidewire hole extends along the insertion direction;
The endoscope according to claim 2. The lens is arranged to form an image of the imaging light on the light receiving surface,
In a direction orthogonal to the optical axis of the lens , the cross-sectional outer diameter of the lens is larger than the cross-sectional outer diameter of the sensor circuit unit ,
The endoscope according to any one of claims 1 to 3 . Insulation resistance between the conductive member and the grounding member is smaller than insulation resistance between the sensor circuit unit and the conductive member,
The endoscope according to any one of claims 1 to 4 . The grounding member is a metal wire,
The endoscope according to any one of claims 1 to 5 . The sensor circuit section has a plurality of bumps provided on the back surface, and a plurality of core wires electrically connected to the plurality of bumps and extending along the insertion direction,
The endoscope according to any one of claims 1 to 6.

Images